diff --git a/meta-digi-dey/recipes-connectivity/btfilter/files/bluez-init b/meta-digi-dey/recipes-connectivity/btfilter/files/bluez-init
index 5d5dbb6dc..460d5b2b3 100755
--- a/meta-digi-dey/recipes-connectivity/btfilter/files/bluez-init
+++ b/meta-digi-dey/recipes-connectivity/btfilter/files/bluez-init
@@ -21,112 +21,86 @@ if [ "${1}" != "start" ]; then
 	exit 0
 fi
 
-SCRIPTNAME="$(basename ${0})"
+SCRIPTNAME="$(basename "${0}")"
 
 bt_init() {
-	#
 	# Exit if this hardware does not support Bluetooth
-	#
 	if [ "${MACHINENAME}" = "ccardimx28" ]; then
-		BLUE_TOOTH_VARIANTS="0x02 0x03 0x10 0x11"
+		BLUETOOTH_VARIANTS="0x02 0x03 0x10 0x11"
 		MOD_VARIANT="$(cat /proc/device-tree/digi,hwid,variant 2>/dev/null || \
-			       cat /sys/kernel/${MACHINENAME}/mod_variant)"
-		if ! echo ${BLUE_TOOTH_VARIANTS} | grep -qs ${MOD_VARIANT}; then
+			       cat "/sys/kernel/${MACHINENAME}/mod_variant")"
+		if ! echo "${BLUETOOTH_VARIANTS}" | grep -qs "${MOD_VARIANT}"; then
 			echo "${SCRIPTNAME}: variant ${MOD_VARIANT} does not support bluetooth"
 			exit
 		fi
 		BT_PWR_GPIO_NR="21"
 	elif [ "${MACHINENAME}" = "ccimx6sbc" ]; then
-		BLUE_TOOTH_VARIANTS="0x02 0x03 0x04 0x06"
+		BLUETOOTH_VARIANTS="0x02 0x03 0x04 0x06"
 		MOD_VARIANT="$(cat /proc/device-tree/digi,hwid,variant)"
-		if ! echo ${BLUE_TOOTH_VARIANTS} | grep -qs ${MOD_VARIANT}; then
+		if ! echo "${BLUETOOTH_VARIANTS}" | grep -qs "${MOD_VARIANT}"; then
 			echo "${SCRIPTNAME}: variant ${MOD_VARIANT} does not support bluetooth"
 			exit
 		fi
 		BT_PWR_GPIO_NR="244"
 	fi
 
-	#
-	# Get the Bluetooth MAC address from NVRAM. Use a default value if the
-	# address has not been set.
-	#
-	if [ -f "/proc/device-tree/bluetooth/mac-address" ]; then
-		BTADDR="$(hexdump -ve '1/1 "%02X" ":"' /proc/device-tree/bluetooth/mac-address | sed 's/:$//g')"
-	else
-		BTADDR="$(sed -ne 's,^.*btaddr1=\([^[:blank:]]\+\)[:blank:]*.*,\1,g;T;p' /proc/cmdline)"
-	fi
-	if [ -z "${BTADDR}" -o "${BTADDR}" = "00:00:00:00:00:00" ]; then
-		BTADDR="00:04:F3:FF:FF:BB"
-	fi
+	# Use a sub-shell here to change to firmware directory
+	(
+		cd /lib/firmware/ar3k/1020200
 
-	#
-	# We need to write the Bluetooth MAC address to ar3kbdaddr.pst in
-	# the AR3k firmware directory.  However, we don't want to rewrite the
-	# file if it already exists and the address is the same because we
-	# don't want to wear out NAND flash. So compare the two and only
-	# update the copy on NAND if the address has changed.
-	#
-	FW_MAC="/lib/firmware/ar3k/1020200/ar3kbdaddr.pst"
-	[ -f "${FW_MAC}" ] && [ "$(cat ${FW_MAC})" = "${BTADDR}" ] || echo ${BTADDR} > ${FW_MAC}
-
-	BT_CONFIG_FILE="/lib/firmware/ar3k/1020200/PS_ASIC.pst"
-	BT_CLASS_1_FILE="/lib/firmware/ar3k/1020200/PS_ASIC_class_1.pst"
-	BT_CLASS_2_FILE="/lib/firmware/ar3k/1020200/PS_ASIC_class_2.pst"
-	BT_READ_ME="/lib/firmware/ar3k/1020200/readme.txt"
-	#
-	# It is illegal to operate a class 1 Bluetooth device in Japan.  So see
-	# if this is a Japanese unit, and, if so, make sure it is configured
-	# for class 2 Bluetooth.
-	#
-	JAPANESE_REGION_CODE="0x2"
-	REGION_CODE="$(cat /proc/device-tree/digi,hwid,cert 2>/dev/null || \
-		       cat /sys/kernel/${MACHINENAME}/mod_cert)"
-	if [ -n "${REGION_CODE}" -a "${JAPANESE_REGION_CODE}" = "${REGION_CODE}" ]; then
-		#
-		# We don't want to wear out flash rewriting the configuration file,
-		# so only replace the configuration file if it is not the class 2
-		# version.
-		#
-		if ! cmp -s ${BT_CLASS_2_FILE} ${BT_CONFIG_FILE}; then
-			ln -sf $(basename ${BT_CLASS_2_FILE}) ${BT_CONFIG_FILE}
+		# Get MAC address from device tree or NVRAM. Use a default value it it has not been set.
+		if [ -f "/proc/device-tree/bluetooth/mac-address" ]; then
+			BTADDR="$(hexdump -ve '1/1 "%02X" ":"' /proc/device-tree/bluetooth/mac-address | sed 's/:$//g')"
+		else
+			BTADDR="$(sed -ne 's,^.*btaddr1=\([^[:blank:]]\+\)[:blank:]*.*,\1,g;T;p' /proc/cmdline)"
+		fi
+		if [ -z "${BTADDR}" ] || [ "${BTADDR}" = "00:00:00:00:00:00" ]; then
+			BTADDR="00:04:F3:FF:FF:BB"
 		fi
-		#
-		# We don't want the Bluetooth police to drag away our Japanese
-		# users, so delete the class 1 configuration file and the readme
-		# file that refers to it.
-		#
-		rm -f ${BT_CLASS_1_FILE} ${BT_READ_ME}
-	elif [ ! -e ${BT_CONFIG_FILE} ]; then
-		#
-		# Default to class 1 Bluetooth for non-japanese users.
-		#
-		ln -sf $(basename ${BT_CLASS_1_FILE}) ${BT_CONFIG_FILE}
-	fi
 
-	#
+		# Update the MAC address file only if it has changed.
+		FW_MAC="ar3kbdaddr.pst"
+		[ -f "${FW_MAC}" ] && [ "$(cat ${FW_MAC})" = "${BTADDR}" ] || echo ${BTADDR} > ${FW_MAC}
+
+		JPN_REGCODE="0x2"
+		REGCODE="$(cat /proc/device-tree/digi,hwid,cert 2>/dev/null || \
+			   cat "/sys/kernel/${MACHINENAME}/mod_cert")"
+		BT_CLASS_LINK="PS_ASIC.pst"
+		BT_CLASS_FILE="PS_ASIC_class_1.pst"
+		if [ -n "${REGCODE}" ] && [ "${JPN_REGCODE}" = "${REGCODE}" ]; then
+			BT_CLASS_FILE="PS_ASIC_class_2.pst"
+		fi
+
+		# Replace the configuration file if different
+		if ! cmp -s ${BT_CLASS_FILE} ${BT_CLASS_LINK}; then
+			ln -sf ${BT_CLASS_FILE} ${BT_CLASS_LINK}
+		fi
+		# Remove not used configuration and readme files
+		# -- Do not quote the subcommand to avoid leading/trailing whitespace
+		# -- being part of the file name.
+		rm -f $(echo PS_ASIC_class_?.pst | sed -e "s,${BT_CLASS_FILE},,g") readme.txt
+	)
+
 	# Start the Bluetooth driver and daemon (D-BUS must already be running)
-	#
-	HCIATTACH_ARGS="ttyBt ath3k 4000000"
 	RETRIES="5"
 	while [ "${RETRIES}" -gt "0" ]; do
-		hciattach ${HCIATTACH_ARGS} 1>/dev/null && break
+		hciattach ttyBt ath3k 4000000 1>/dev/null && break
 		#
 		# If hciattach fails try to recover it by toggling the GPIO
 		#
 		BT_PWR_L="/sys/class/gpio/gpio${BT_PWR_GPIO_NR}"
-		[ -d "${BT_PWR_L}" ] || echo -n ${BT_PWR_GPIO_NR} > /sys/class/gpio/export
-		echo -n out > ${BT_PWR_L}/direction && sleep .2
-		echo -n 0 > ${BT_PWR_L}/value && sleep .2
-		echo -n 1 > ${BT_PWR_L}/value && sleep .2
-		[ -d "${BT_PWR_L}" ] && echo -n ${BT_PWR_GPIO_NR} > /sys/class/gpio/unexport
+		[ -d "${BT_PWR_L}" ] || printf "%s" ${BT_PWR_GPIO_NR} > /sys/class/gpio/export
+		printf out > ${BT_PWR_L}/direction && sleep .2
+		printf 0 > ${BT_PWR_L}/value && sleep .2
+		printf 1 > ${BT_PWR_L}/value && sleep .2
+		[ -d "${BT_PWR_L}" ] && printf "%s" ${BT_PWR_GPIO_NR} > /sys/class/gpio/unexport
 		RETRIES="$((RETRIES - 1))"
 	done
 	if [ "${RETRIES}" -eq "0" ]; then
 		echo "${SCRIPTNAME}: FAILED (hciattach)"
 		exit
 	fi
-	BT_FILTER_ARGS="-b -x -s -w wlan0"
-	if ! abtfilt ${BT_FILTER_ARGS} 1>/dev/null; then
+	if ! abtfilt -b -x -s -w wlan0 1>/dev/null; then
 		echo "${SCRIPTNAME}: FAILED (abtfilt)"
 		exit
 	fi